U.S. Federal Communications Commission Chairman Julius Genachowski said an impending shortage of wireless spectrum in the U.S. will dampen future economic growth unless action is taken to fix the problem.

"Our data shows there's a looming crisis, not tomorrow, not next week, not next year, but at some point in the future," Genachowski told attendees at the International Consumer Electronics Show (CES) in Las Vegas on Friday.

"The record is pretty clear that we need to find more spectrum," he said.

The FCC has identified the limited supply of wireless spectrum as one of the factors that could limit the growth of broadband Internet services in the U.S., which could result in slower economic growth and job creation.

Wireless spectrum will be addressed, along with other factors affecting broadband access and services, in a national broadband plan that the FCC is now assembling. The plan was originally due to be completed next month, but the FCC received a 30-day extension from the U.S. Congress.

The wide array of devices on display at CES that rely on wireless broadband underscores the urgency of resolving the spectrum issue, Genachowski said.

"The wireless infrastructure in the U.S. will be our platform for ongoing innovation and investment," he said.

Genachowski declined to detail specific goals of the upcoming national broadband plan but said the FCC will make more spectrum available. However, allocating enough spectrum to meet projected demand will require freeing up spectrum that is currently assigned to users in the private sector and government, a process that has taken from six years to 13 years to complete in the past, he said.

Given the urgency of the problem, the FCC will have to move quickly to avoid demand for wireless broadband outstripping the supply of available spectrum, Genachowski said, adding that other measures are needed to ensure that wireless networks are used as efficiently as possible.

"We're in a period where we need to look at everything we can do to incentivize and encourage more efficient use of this limited resource," he said.

One way to more efficiently use spectrum is to encourage a secondary market where licensees can easily rent out to other organizations spectrum that they may not be using. That's one idea that the U.S. Department of Justice recently recommended to the FCC in a filing encouraging the agency to move quickly to free up more spectrum.